Effect of Citrus Flavonoids on Obesity.

Not Applicable

Completed

• Conditions: Obesity Adult Onset; Diabetes Mellitus Type 2

• Registration Number: NCT06680635
• Lead Sponsor: Celia Bañuls

Brief Summary

The aim of this study is to evaluate whether the intake of a functional juice enriched in citrus polymethoxylated flavonoids is able to improve the glycaemic profile and insulin resistance of obese patients by reversing the associated oxidative and inflammatory stress, as well as the differential alteration of the intestinal microbiota. To achieve this, a prospective, randomised, double-blind, placebo- controlled, clinical-baseline intervention study will be conducted in obese patients (BMI=30-40 kg/m2) with type 2 diabetes (DM2) (n=40) and obese patients without alterations in carbohydrate metabolism (n=40). Each of these groups will be randomly divided into 2 subgroups (n=20), one of which will receive polymethoxyflavonoid-enriched orange juice (14%: nobiletin, sinensetin, tangeretin) (200 ml/ day) and the other group will receive the corresponding placebo juice for 8 weeks. In addition, all of them will receive a hypocaloric diet. Anthropometric parameters, body composition and nutritional status will be assessed, cardiovascular risk factors and comorbidities will be studied (HT, SAHS, dyslipidaemia, insulin resistance), oxidative stress parameters will be compared (total and mitochondrial ROS production, mitochondrial membrane potential, glutathione levels by static cytometry and mitochondrial respiration rate by Seahorse flow analyser), antioxidant enzymes (SOD, GPx) and molecular oxidation products (Carbonyl proteins and 8-oxo-dG, LDLox) and LPS by ELISA techniques, inflammatory parameters (IL6, TNFa, IL1b, adiponectin, PAI-1, IL10) by Luminex XMAP technology in serum. Metabolomic analysis will also be performed in plasma (NMR spectroscopy and PLS-DA), and the content and diversity of the gut microbiota (16S rRNA amplicons, and direct metagenomic sequencing, with Illumina MiSeq technology) will be assessed in faeces, before and after the dietary intervention. Individualised dietary follow-up and assessment of subjects' quality of life will be carried out.

Detailed Description

Not available

Study Timeline

• Study Start: 2022-01-01
• Study First Submitted: 2024-11-06
• Study First Submitted QC: 2024-11-07
• Study First Posted: 2024-11-08
• Primary Completion: 2024-12-31
• Study Completion: 2025-01-31
• Status Verified: 2025-02
• Last Update Submitted: 2025-02-25
• Last Update Posted: 2025-02-27

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

• patients with a BMI of 30 -40 kg/m2, between 18 and 65 years of age.
• Obesity of more than five years' duration
• Patients will maintain a stable weight (±2 kg) during the 3 months prior to the study.

Exclusion Criteria

• Patients with acute or chronic inflammatory diseases and established liver and kidney failure (based on transaminase levels ±2 SD of the mean and estimated glomerular filtration rate using the CKD-EPI formula >60), neoplastic diseases and secondary causes of obesity (hypothyroidism, Cushing's syndrome), use of drugs that may influence inflammatory status or insulin sensitivity (NSAIDs, corticosteroids, anti-TNFα), treatment with insulin or GLP1 inhibitors, type 1 diabetes, morbid obesity (BMI>40 kg/m2), hypertriglyceridaemia (> 400 mg/dl), fructose intolerance.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
To evaluate insulin resistance index	5 years	Evaluate if there is an improvement in insulin resistance levels after the intervention depending on the intake of a flavonoid-enriched juice or its corresponding placebo for 6 weeks, in obese patients without alterations in carbohydrate metabolism and obese patients with type 2 diabetes (DM2).; HOMA-IR will be used. Participants will be considered to have achieved an improvement in insulin resistance levels if they normalize its value (normality values defined between 0 and 3.8 units).
Analyze the significant differences between metabolomic profile before and after the dietetic intervention, and between both groups (flavonoid-enriched juice vs placebo)..	5 years	NMR spectra will be used to obtain spectra from serum samples from the cohort. In order to evaluate if there will be significant differences after the dietetic intervention, a PLS-DA model for discrimination between basal and post intervention levels will be performed. Scores plots will be calculated with a 95% confidence interval.

Secondary Outcome Measures

Name	Time	Method
Assess significant changes in body fat mass percentage after the dietetic intervention.	5 years	Percentage of body fat mass will be measured by bioelectrical impedance. It is considered to be high when ≥25% in men and ≥30% in women. A significant improvement will be considered when notable differences are observed in the mean values between groups (flavonoid-enriched juice vs. placebo) measured through p-value (\<0.05) with a 95% confidence interval.
To assess significant changes in triglycerides before and after the use of flavonoid-enriched juice and its placebo in the same groups of patients.	5 years	Participants will be considered to have achieved an improvement in plasmatic triglycerides level if they normalize its value (normality values defined between 0 and 150mg/dL).
To evaluate the composition and diversity of gut microbiota	5 years	To evaluate the diversity of gut microbiota in faeces (measured by alpha-diversity) before and after the use of a flavonoid-enriched juice and its placebo in the same groups of patients.; To asses the differences in alpha-diversity of the intestinal microbiota in both groups, it will be evaluated whether there are significant differences between the Shannon indices of the two groups. The results are interpreted as follows: values less than 2 are considered low in diversity and values greater than 3 are high in species diversity.
To identify serum biomarkers using a metabolomic approach	5 years	To identify serum biomarkers using a metabolomic approach before and after intervention with flavonoid-enriched juice or placebo in the same groups of patients. NMR spectra will be used to obtain spectra from serum samples from the cohort. In order to evaluate if there will be significant differences after the dietetic intervention (according to the flavonoid-enriched juice or placebo intake), a PLS-DA model for discrimination between basal and post intervention levels will be performed. Scores plots will be calculated with a 95% confidence interval.
Evaluate significant changes in % of weight loss after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
To assess significant changes in LDLc before and after the use of flavonoid-enriched juice and its placebo in the same groups of patients.	5 years	Participants will be considered to have achieved an improvement in serum cLDL levels if they normalize its value (normality values defined between 0 and 130mg/dL).
To assess significant changes in HDLc before and after the use of flavonoid-enriched juice and its placebo in the same groups of patients.	5 years	Participants will be considered to have achieved an improvement in serum cHDL levels if they normalize its value (normality values defined between 45 and 70mg/dL in women, and 40 to 70mg/dL in men).
Evaluate significant changes in high-sensitivity C-reactive protein (hs-CRP) after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Participants will be considered to have achieved an improvement in high-sensitivity C-reactive protein levels if they normalize its value (normality values defined between 0 and 1.69mg/dl).
Assess significant changes in C3 protein after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Participants will be considered to have achieved an improvement in C3 protein if they normalize its value (normality values defined between 81 and 157mg/dl).
Evaluate significant changes in plasmatic homocysteine as a inflammatory parameter after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Participants will be considered to have achieved an improvement in plasmatic homocysteine if they normalize its value (normality values defined between 5 and 15µmol/L).
Assess significant changes in interleukin 1-beta (IL-1B) levels as a pro-inflammatory molecule after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	IL-1B levels will be measured using the Luminex® 200 analyzer system. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Evaluate significant changes in interleukin 6 (IL-6) levels as a pro-inflammatory molecule after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	IL-6 levels will be measured using the Luminex® 200 analyzer system. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Assess significant changes in tumor necrosis factor alpha (TNF-alpha) levels as a pro-inflammatory molecule after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	TNF-alpha levels will be measured using the Luminex® 200 analyzer system. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Evaluate significant changes in superoxide dismutase (SOD) levels as a pro-inflammatory molecule after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Superoxide dismutase levels will be measured using the Luminex® 200 analyzer system. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Evaluate significant changes in ROS levels after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Total ROS levels will be assessed by a flow cytometry assay. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Assess significant improvements in glutathione levels after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Total glutathione levels will be assessed by a flow cytometry assay. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Assess significant improvements in total free radicals and superoxide levels after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Total free radicals and superoxide content will be assessed by a flow cytometry assay. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Evaluate significant improvements in mitochondrial ROS production after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Mitochondrial ROS production will be assessed by a flow cytometry assay. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.
Analyze significant improvements in mitochondrial membrane potential after the dietetic intervention in both groups (flavonoid-enriched juice vs placebo) after the dietary intervention.	5 years	Mitochondrial membrane potential will be assessed by a flow cytometry assay in PBMCs. A significant improvement will be considered when notable differences are observed in the mean values between groups measured through p-value (\<0.05) with a 95% confidence interval.

Trial Locations

Locations (1)

FISABIO; 🇪🇸 Valencia, Spain